In the vertical packaging machines of known type a suitable forming device creates, with a sheet starting from a strip, a vertical tube subjected to transversal sealing at predetermined spacing.
After making a transversal seal which closes a section of the tube, the product to be packaged is introduced by gravity into the tube before performing the subsequent transversal sealing.
The tube is then cut transversely at the transversal sealing zones to detach the pack from the tube.
These vertical packaging machines require a considerable use of packaging material since, to prevent the product to be packaged from becoming stuck in the tube whilst it is being lowered, the tube must have a diameter greater than the maximum outside dimension of the product.
The diameter of the tube is also over-sized to allow the escape of air which could otherwise become trapped between the falling product and the cross section of the tube closed by the transversal sealing.
There are also horizontal forming, filling and sealing packaging machines (in jargon called “Form, fill and seal” or “flow pack”), commonly used in the sector of packaging capsules for portioned beverages, particularly coffee capsules.
In these packaging machines a tubular sheet is positioned horizontally and the capsules are simply rested inside it at predetermined reference positions.
In this case, to create a pack wherein the container contains the capsule immersed in an atmosphere of protective inert gas, the tube is subjected to transversal sealing at predetermined spacing whilst a flow of inert gas passes through which fills it whilst expelling at the same time the atmospheric air contained.
To prevent the capsules from moving from their correct reference position during the flow of gas, an over-sizing of the diameter of the tube is necessary, to eliminate the possible occurrence of excessive overpressures inside the tube due to the obstacle created by the capsules to the circulation of the gas.
This embodiment for the capsule making machine also determines a considerable waste of packaging material which, as in the case described above, has a negative effect on the cost of the pack.
As well as the considerable waste of packaging material there is an equally significant waste of inert protective gas necessary for filling the more voluminous packs.
These packs, because of how they are made, therefore have an overall size which is considerably greater than the size of the capsule which they contain.
This also adversely affects the logistics as very containers are required for arranging a predetermined number of packs, with obvious negative repercussions on the storage and transport costs.